The Drake LF-2(shown) provides a good deal of line voltage protection for your R7A. The LF-2 low pass AC line filter restricts RF signals from travelling the AC power lines. It also has a hash filter and transient suppressor (GE V220MA4B MOV). One grounded duplex outlet is provided. A #10 bolt is affixed to the case for grounding. The LF-2 is housed in a black anodized aluminum enclosure. 5.4 x 2.4 x 1.7 inches. 8 Amps.

The Drake LF-6 features six AC outlets and has an illuminated rocker-type power switch. 16.2 x 2.4 x 1.7 inches. (Not shown).